A case of herpes zoster myelitis: positive magnetic resonance imaging finding

Herpes zoster cervical myelitis in a young adult

Varicella zoster virus infection, which causes chickenpox and herpes zoster (HZ), is not uncommon in the general population. Varicella zoster virus can be latent in cranial nerve or dorsal root ganglia, and reactivate several decades later to produce vesicles with post-herpetic neuralgia. HZ myelitis usually occurs in elderly or immunocompromised patients. We report here a case of HZ myelitis of the cervical spinal cord in a 35-year-old woman who was immunocompetent. Cervical myelitis developed 1 month after the eruption of vesicles. Pure sensation loss was limited initially from the C2 to T1 dermatomes, but later progressed to lower limb sensory loss and sphincter function impairment. The patient's motor function was also mildly affected. Despite the initial rapid neurological deterioration, the symptoms dramatically improved after 5 days of parenteral acyclovir and steroid administration with rehabilitation. We therefore propose that early medical intervention is necessary for better and earlier recovery.

Central nervous system infections of herpesvirus family

Herpesviruses are one of the most common groups of pathogens causing central nervous system infections in humans. They mostly cause encephalitis, meningitis, or myelitis in immunocompetent and immunocompromised patients. Children, adults, and the elderly can all be affected. Although contrast-enhanced CT is more widely used for diagnosis, contrast-enhanced MR imaging combined with diffusion-weighted imaging is superior to CT in the detection of early changes and the real extent of the disease, and in assessing prognosis and monitoring response to antiviral treatment. More sophisticated techniques, such as MR spectroscopy and perfusion imaging, can aid in the differential diagnosis of herpesvirus infections from other tumoral, demyelinating, and ischemic processes.

Recommendations for the management of herpes zoster

The objective of this article is to provide evidence-based recommendations for the management of patients with herpes zoster (HZ) that take into account clinical efficacy, adverse effects, impact on quality of life, and costs of treatment. Systematic literature reviews, published randomized clinical trials, existing guidelines, and the authors' clinical and research experience relevant to the management of patients with HZ were reviewed at a consensus meeting. The results of controlled trials and the clinical experience of the authors support the use of acyclovir, brivudin (where available), famciclovir, and valacyclovir as first-line antiviral therapy for the treatment of patients with HZ. Specific recommendations for the use of these medications are provided. In addition, suggestions are made for treatments that, when used in combination with antiviral therapy, may further reduce pain and other complications of HZ.

Herpes zoster of the head and limbs: electroneuromyographic and clinical findings in 158 consecutive cases

OBJECTIVES

To quantify electromyographic and neurographic changes and to correlate them with the clinical data of outpatients with herpes zoster.

DESIGN

Prospective case series.

SETTING

Outpatient department.

PATIENTS

A consecutive, unselected series of 158 outpatient cases (88 women, 70 men; mean age, 64y) of herpes zoster of the head and limbs.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Blink reflex and electromyography and motor and sensory nerve conduction velocities of nerves and muscles corresponding to affected dermatomes.

RESULTS

Postherpetic neuralgia (PHN), segmental zoster paresis, and polyneuropathy were found in 31%, 19%, and 2.5% of cases, respectively. Absence or reduction of sensory action potential amplitudes, blink reflex areas, and compound muscle action potential amplitudes were found in 60%, 31%, and 18% of cases, respectively. Sensory and motor conduction velocities and motor and blink reflex latencies were nearly always normal or only slightly slowed. Electromyographic signs of abnormal spontaneous activity were found in 36% of the cases. Electrophysiologic alterations were correlated among themselves, with age, with presence of segmental zoster paresis, and with absence of antiviral therapy. The extent of the skin rash (number of dermatomes affected by herpes zoster) was the only variable predictive of disappearance or improvement of PHN.

CONCLUSIONS

Sensory axonal neuropathy, often associated with similar motor involvement, can be shown by classical electrophysiologic methods in herpes zoster. The severity of damage to motor fibers was related to damage to sensory fibers, but no relation was found between peripheral axon damage and PHN. The site of motor system damage may be the ventral roots, plexus, or peripheral nerve. The probability of complications and the severity of sensory and motor peripheral axonal damage were increased in older patients. Appropriate antiviral therapy seems to reduce the incidence of segmental zoster paresis and the severity of damage to the peripheral fibers. A reduced extent of herpetic rash was the only factor to correlate with a good outcome of PHN.

Magnetic resonance imaging findings in 22 cases of myelitis: comparison between patients with and without multiple sclerosis

We reviewed the magnetic resonance imaging (MRI) database of the Dent Neurologic Institute to study the abnormal findings in myelitis. We identified 22 patients, and compared non-MS-related acute transverse myelitis (ATM, n = 9), to myelitis associated with multiple sclerosis (MS-myelitis, n = 13). The ATM patients were significantly older than MS patients at the time of the myelitis diagnosis (mean age 46 vs 35, p < 0.05). ATM appeared as a "longitudinal myelitis", with fusiform cord expansion on T1-weighted images and intramedullary increased signal on T2-weighted images, each involving multiple spinal levels (mean = 7-8). However, MS-myelitis lesions appeared focal, involving significantly fewer spinal levels (mean = 1-2, p < 0.001), although the lesions were equally likely to expand the cord. Four (42%) of the ATM lesions showed abnormal, variable enhancement, whereas none of the MS myelitis lesions enhanced. Cranial MRI was more likely to be normal in ATM (78%) than in MS-myelitis patients (15%, p < 0.001). Although readily distinguishable from lesions due to MS, the various etiologies for ATM, including post-infectious (n = 2), post-vaccination (n = 3), and idiopathic (n = 4) were indistinguishable on MRI. The MRI findings of an extensively lesioned, swollen cord, suspicious for an intramedullary tumor and providing a temptation for a biopsy, may reflect a non-neoplastic inflammatory disorder.

Acute infectious disorders of the spinal cord and its roots with gadolinium-DTPA enhancement in magnetic resonance imaging

We studied three patients with myelomeningoradiculitis caused by Borrelia burgdorferi, herpes zoster virus or cytomegalovirus infection. All patients underwent MRI of the spinal cord with gadolinium-DTPA and showed enhancing lesions of the spinal cord or nerve roots that correlated with clinical signs. Gadolinium-DTPA enhancement may visualize lesions that suggest an inflammation associated with blood-brain-barrier alteration and indicate the diagnosis before serological results are available.